### Alliance of Automobile Manufacturers Testimony on EPA’s Proposal to
Retain the National Ambient Air Qua lity Standards for Carbon Monoxide 76 Fed. Reg. 8158 (February 11, 2011)

February 28, 2011

My name is Giedrius Ambrozaitis and I am here today representing the Alliance of Automobile Manufacturers. The Alliance is an association of 12 vehicle manufacturers including BMW Group, Chrysler Group LLC, Fo rd Motor Company, General Mo tors Company, Jaguar Land Rover, Mazda, Mercedes-Benz USA, Mitsubishi Motors, Porsche, Toyota, Volkswagen Group

of America and Volvo.

The Alliance members recognize the importance of ensuring clean air and setting air quality standards at a level that prot ects public health. Our air is cleaner today than it was a generation ago, and air quality is continuing to improve.

Our nation’s air is getting cleaner even as our economy grows and vehicles travel more and more miles. According to EPA’s most recent air trends analysis 1 , since 1990, nationwide air quality has improved significantly for the six comm on air pollutants. Nationally, over this time period, ozone has decreased 14 percent, fine particulate matter has decreased 19 percent, nitrogen dioxide has decreased by 35 percent, sulf ur dioxide has decreased by 59 percent and carbon monoxide has decreased by 68 percent. Investments and improvements in vehicle technology and manufacturing processes are a ma jor part of this success story. Today's

vehicles are 99% cleaner than vehicles of the 1970s, thanks to dramatic reductions in smogforming emissions.

Further, significant additional emission reductions will occur over the next 20 years as a result of already promulgated regulatio ns for mobile sources. Acco rding to EPA’s own statistics, emissions from cars and trucks are expected to be reduced by an additional 70 percent by 2030. These reductions will help to reduce criteria pollutant concentrations across the country, and the improvements to air quality as a result of these reductions will continue to occur.

1 EPA, Our Nation’s Air

– Status and Trends Through 2008, available at h ttp://www.epa.gov/airtrends/2010The Alliance supports EPA’s proposal to retain t he current levels of 9 ppm over 8 hours and 35 ppm measured over 1 hour for the carbon m onoxide NAAQS standard. As EPA notes, the science shows that the current standards will pr otect people, especially those susceptible to health problems associated with breathing CO from the outdoor air. We agree with EPA’s

conclusion that the current st andard provides a very high de gree of protection for the carboxyhemoglobin (COHb) levels and associated he alth effects of concern. The current suite of standards provides an adequate margin of safe ty against adverse effects associated with shortterm ambient CO exposures. The Allia nce agrees with the Administrator that the

uncertainties and limitations of the epidemiological ev idence are too great to provide a basis for revising the current standards. We note that retaining the current standards is also

consistent with the advice EPA received from C ASAC, EPA’s own scientific advisory panel.

As I noted, EPA’s monitoring data indicates t hat ambient carbon monoxide concentrations

continue to fall as cleaner and cleaner vehicles enter the fleet. EPA’s w ebsite indicates that

carbon monoxide levels decreased 80 % between 1980 and 2009. The ambient levels of CO have continued their steady decline over t he past several years. From 2001 to 2008,

concentrations of 8-hour ca rbon monoxide decreased 41%. T here are currently no areas designated as nonattainment.

The Alliance is still evaluating EPA’s proposal to revise the air monitoring requirements for CO. Our initial reaction is that the proposal needs fu rther consideration. As the proposal notes, the monitoring of CO in peak microscale locati ons has been a high priority since 1979. The proposal to move existing monitors to be co-located with near-roadway NO 2 monitors raises several questions and concerns. The locations of these monitors will be close to the most heavily travelled segments of t he most heavily travelled expressways. As such, this approaches peak source monitoring rather than moni toring locations that represent population

exposures.

Monitors should be located where there are people exposed to peak 1-hour or 8-hour CO concentrations. However, the proposal does not include a requirement that the monitoring sites be locations where people are actually ex posed to CO for such times. It should.

If non-attainment is determined at a proposed nea r-road microscale site, which has a spatial scale of representativeness of from a few meters up to 100 meters, what is the size of the nonattainment area that would be designated? Since the location is dominated by the traffic source, what kind of a SIP would be required? Since the current motor vehicle regulatory program will continue to reduce on-road emissions , would the requirement to develop a SIP be
redundant and wasteful? Questions such as t hese need to be considered by the Agency

before the rule is finalized.

The proposal lists several benefits from the pr oposed changes to the monitoring network. One

benefit noted is that the overa ll network would be smaller. The Alliance is concerned, however, that with the proposed changes on top of the movement of si tes to the new NCore monitoring network, the nation will lose many sites that can be used to determine nationwide trends. Maintaining a consistent set of sites to determine long te rm trends should be a priority for the Agency.Another benefit listed is that the sites will provide data that can support health studies. However, fixed microscale sites that are located to be close to the very highest traffic density in a city will not be particularly useful for health studies. Personal exposure monitoring of populations that live close to roadways woul d provide much better information on the

distribution of their CO exposures.

The proposal indicates that the data can be used in verification of modeling results. However, to verify modeling results requi res a different study design, one that does not require 77 new

monitors in different cities. A smaller set of well-designed monitors at various distances from the highway along with detailed meteorological measurements around the roadway would be a much better approach to verify roadway dispersion models.

Finally, the proposal indicates t hat the data would useful to estimate in-vehicle on-roadway exposures. Again, a research program to measure such exposur es directly would be a much better method to gather such information.

The Alliance appreciates this opportunity to comment. We will also be submitting written comments on the proposal in April. I would be happy to answer any questions.